Jack-in-the-box

A jack-in-a-box, as ChiefMiles O'Brien phrased it, was "a children's toy, on Earth. You wind it up and a figure jumps out and goes 'Boo!'."

In holo-programming, a jack-in-the-box was a hidden subroutine that a programmer could add to an interactive holosuite program, which was designed to suddenly spring to life, just as the children's toy of the same name, to surprise the user and keep the program from getting boring. However, unlike the children's toy, which merely says, "Boo", a holosuite jack-in-the-box can cause significant chaos to the very program which it is a part of. The results of a jack-in-the-box can lead to the termination or corruption of the program itself.

Although not self-aware, the characters in a jack-in-the-box can be made immune from re-programming and from "freeze program" commands. Therefore, once activated, the subroutine runs in real-time, making it possible for events to transpire without any real-world (non-holographic) character being present. Jack-in-the-box characters can be made "period-specific", meaning that only items and methods available in the program's universe are usable against the character (thus, a phaser would have been useless against a period-specific 1960sgangster).

Often, the designer of a jack-in-the-box will include an "out" (that is, a way to beat the jack-in-the-box). This "out" must be accomplished within the boundaries of the program's universe. The opportunity to reach an "out" may also expire, since the characters in a jack-in-the-box are "existing" in real-time, and potentially changing the components of their own existence.

Frankie Eyes, a mobster with a deep-seated grudge against Vic, as well as muscleman Tony Cicci sprang into "existence," and took over Vic's lounge. Backed by the wealthy, yet equally corrupt, Mr. Zeemo, they threatened Vic's very existence in the program, and were only defeated by the combined effort of the space station's senior staff in 2375. (DS9: "Badda-Bing, Badda-Bang")